Method of treating material in a vacuum and apparatus



A2l 22 m O. MINTON l Il".

origina-1 Filed March 4, 1920 METHOD OF TREATING MATERIAAL IN A VACUUM AND APPARATUS Aug. 10 1926.

A TTORNEY Z A Z Patented hugo 1Q, 1926.

um STATES. PATENT OFFICE.

GDEN MINTON, OF GREENWICE, CONNECTICUT.

METHIOD 0F '.IRIEATINGl MATERIAL IN A VACUUM AND A'PPAIRl TUS.

originai application inea march 4, 1920, serial mi. $63,849. Divided and this application ined Haren ao,

1922, Serial No. 545,215.

This application is a division of my copending Vapplication. Method of treating material in a vacuum and apparatus, filed March 4, 1920, Ser. No. 863,349, Case E. 1

The present invention relates to an apparatus and method for coating or coloring, or sizing or impregnating pa sheet material, in a vacuum c amber, and drying said sheet material in the vacuum chamber before it is again subjected to the atmosphere. r

My improved methodconsists inpassing the sheet material which is to be coated, colored, sized or im regnated into a vacnum chamber throug a liquid sealing medium which has no afHnity for the material, then coating, coloring, sizing or impregnating the paper or other sheet material while in -the vacuum chamber, then drying the coated, colored, sized, or impregnated sheet material while still in the vacuum. vchamber, and then passing the dried material out of the vacuum chamber through a seal.

My invention further relates to obtaining a better and more uniform product than anyv now known on the market. My invention further relates tothe method of coating or implregnating sheet material which insures t at there will be no blemishes, uneven surfaces, blisters or minute raised ortions due to the air which may be heldp or occluded within the sheet material which, in the present practice of' f matted together on the wire of the paper coating as for example with a water-proc compound, leads to rejections or discards due to these imperfections with the consequent waste of material and labor.

My invention further relates to the. treatnient of paper and coating or impregnating it in a vacuum the vacuum, and' drying it within said vac'- uum chamber.

My invention further relates to manufacturing Apaper wherein the fibers are not weakened andthe size in the paper is not iniured or damaged due to drying at high temperatures.

Tiffy 'invention further relates to manufeaturing colored paper and drying it without substantially impairing the coloring matter and mordants used in the paper. Among other advantages this insures that the paper will have bright'colors, which er or otherchamber, without breaking.

Renewed December 18, 1925.

will be substantially uniform in different runs of paper, permitting matching of colored 'paper without any appreciab e difference in tone or color. My invention further relates to rapidly and expeditiously coating or impregnating sheet material in a continuous web or sheet. My invention further relates to sizing paper in a vacuum chamber and drying 'the sized paper insaid vacuum chambe'mat such low temperatures as not to injure the bers of the paper or-.the size. My 1nvention furyther relates to withdrawing the occluded air from the paper and immediately filling the interstices normally illedwi'th 'the ocunder more than 'sutiicient tension to just feed it through the vacuum chamber. That is, the web of paper is not put under suiiicient tension to substantially rearrange its bers, as thoseV fibers were interlaced or machine. Where the web is put under tension in fdrying, these fibers `are pulled out in 'the direction of travel of the web, which weakensthe web and makes it ofunequal strength. It will be stronger crosswise of the sheetor web than it is lengthwise of the web vor sheet.

In my present invention by letting the fibers dry under little or no tensione-only suilicient to feed the web throughthe vacuum chamberthe bers will not be substantially pulled out or.substantially disarranged from their position as they were on the wire of the paper making machine. .I have termed this' manner of letting the fibers dry under substantially little or no tension as drying at random or at will; distinguishing this method from the common one in which the fibers dry under tension sufiicient to pull lill) them, more or less, from each other and thereby weaken the web or sheet of paper. A web treated according to my method, will form a sheet of paper substantially as strong lengthwise of the sheet 'as it is across the sheet.

My invention :further relates to certain steps, and combinations ot steps, also to certain elements and combinations of elements,

whereby the method or processes herein described may be carried out, as well as to certain details of construction, all ot which will be more fully hereinafter described in the specification and pointed out in the claims.

@t course, my method may be practiced by the use of various forms of apparatus.

In lthe accompanying drawings, which are partly diagrammatic, I have shown for purposes of example two different forms of apparatus.

Fig. 1 isa vertical diagrammatic section;

Fig. 2 is a vertical diagrammaticsection similar to Fig. 1, but showing electric heaters.

In describing m invention, I will describe it as applied to s eet material in the form of paper though it is to be distinctly understood that textile fabrics may also be treated by my process and that my claims cover all forms of sheet materials.

In the ordinary drying of a web of paper such high heat is used as to injuriously affect the fibers of the paper; and in case the paper is colored it will materially aect the coloring matter and mordants used. Drying paper in the high temperatures used in ordinary practice often-affects the size so that the resulting paper varies in quality, is not uniform and is not a perfect product.

In coating or impregnating fabrics it is found in practice that the coated fabric will frequently have blemishes due to large or small blisters and blow holes, these often being about the size of a pin-head or a pinpoint. This is caused by the air which is held or occluded being collected, more or less, in small pockets under the coating or impregnating material, or in some cases caus ing minute blow holes. In water proof fabrics this results in large quantities of the material being rejected with the consequent loss to the manufacturer. y

By my invention I insure that substantially all the occluded airis Withdrawn from the sheet material which Awill permit the coating or im regnating material, Whatever it may be,'to t oroughly lill these minute interstices or pockets normally occupied by occluded'air, forming thereby a better and more uniform product and one devoid ot' blisters, blow holes or such blemishes. By my invention I immediately dry such coatedor impregnated sheet material while still in the vacuum chamber so that when the sheet material emerges from the vacuum chamber the coating or imppregnating material is dry and set withoutiany danger of atmospheric pressure l or atmospheric conditions spoiling or marring the finished product.

- As previously stated, I will describe my invention with relation to coating, coloring or impregnating paper, though it is to be understood that textile fabrics may be treated in the same manner.

The web 1 of paper is fed from the reel or roll 2 over the uide'roll 3 into a liquid seal fl. The liquic? of this seal may be ot' any suitable material which has no atiinity for, or deleterious action upon, either the web 1 as it is iirst fed into the machine or after it has been coated 4or impregnated. I' preferably employ mercugy as thewsealing medium 4, but it is'to bei"distinctlyllunderstood that any amalgarfig'alloy, or any other'N suitable li uid sealing medium may befemployed which has the characteristics abovey specified.

The web is then led over the'guide roll 6 into the coating or coloring or impregnating bath 7 under the submerging roller 8, between the squeeze rolls 9, 9 and over the guide roll 10.

It is now passed through the vacuum chamber A under little or no tension. 'Ihat is just sufhcient tension to feed it through the apparatus but not to substantially rearrange the fibers of the web 1, as those fibers were matted or interlaced on the wire of the paper machine. In this manner, I permit the fibers to dry at will or at random without `being under lsullicient tension to substantiallv rearrange them from the position that they assumed originally up'on the Wire of the paper machine. a

The web ma be fed through the vacuum chamber and ried in any suitable manner provided the fibers are not cause-d to substantially rearrange themselves which weakens, more or less, the web or sheet. I have shown in. Fia. 1 the web .led through the vacuum chamber A in folds or loops passing over the guide rolls 11, 11 and 1'2, 12 until at the end of the vacuum chamber the web passes -over the guide roll 13 and hence out of the liquid seal 4, under the submerging roll 14:, over the guide roller 15 Aand thence can be immediately Wound up into the iinished roll or reel 16.

The web can be heated in any suitable manner. I have shown in Fig. 1 steam or hot water radiators 17, 17 mounted between the folds or loops of the web but at a sutlicient distance to give clearance, the web not touching the radiators. To touch the radiaf tors would cause the web to stick to the radiators and robably cause it to break and foul the mac ine; or, what is known in the trade, as broke to occur.

In Fig. 2 I have shown electric heaters 19,

^ Vapparatus; v

The bath 7 may be heated by steam pipes 20. Thematerial of this bath may plenished vfrom time to time by forcing additional liquid through the lcock 24. The liquidv can also be withdrawn by opening the cock 2d permitting the chamber, in Whic the liquid 7 is mounted, to be cleaned. y

. The vacuum chsimber A is provided with pipes 2l, 2l leading to any suitable vacuum apparatus. l also preferably provide the vacuum chamber with Windows 22, 22 so that the operator can at all times watch the web on its continuous passage' through the vacuum chamber.

eiiiciencies, it

.that about 10,600 pounds are required.

By my process and apparatus the web of sheet material., whether it bepaper or textile material, is rapidly coated or impregnated and immediately dried Within the 'vacuum chamber so that when it emerges the coating or impregnating material 'is dried and set permitting it to be immediately wound into a roll or reel for transportation. v

The thermal eciency of my,vacuum method is very much greater 'than that of the atmospheric cylinder drying heretofore in universal use for dryingpaper. Theoretically, it requires about 5287 -pounds of steam to dry one ton of paper at atmospheric pressure, but to compensate or convection and conduction losses, and those due to leaks in the piping system, and other inhas been shown in practice ln my method using a vacuumofiabout 28, the convection, conduction andpiping losses are exceedingly small and the total steam required to dry a ton of paper by my method is approximately 5200 pounds.

lt is an established fact that paper dried at low temperatures is much stronger than 'when it is driedat the'high temperatures used in paper machine atmospheric drying. Paper dried ina vacuum at 28, or at a temperature of about 100 F., as in my method, is very much stronger thanpaper dried at atmospheric pressure, when the steam in the driers is at 228 F. When paper is dried by my method, therefore, a cheaper furnish can be used and still produce a coated or sized paper equal in strength to atmospheric dried paper, 1n which a higher ade furnish is used. in making newsprlnt paper, l am able to' dispense with a considerable portion ot the more expensive sulphite pulp, as this can be replaced with the cheaper ground Wood pulp. By my method ,I also reduce the number of breaks in the Webl as it passes over the cylinder.

Furthermore, in my method there is a great saving of heat (or steam) because the process is carried on in a vacuum chamber which acts on the principle of a thermos bottle, and the steam and vapors driven out of the wetpaper are caught in the. closed vac-l uum chamber, and conducted away to the condenser. The operating room is free from steam, humidity and heat, and fans, and ex- Vhausters are -dispensed with. In the use of my'method the apparatus is at all times operating under ydefinite humidity,

and the moisture content in the paper care-v fully regulated; Iam 4enabled also lto use a comparatively small mach-ine, whichY takes up comparatively small door space thereby rcd-ucing overhead expenses.

Having pointed out the many advantages of my method and apparatus over those heretofore used, it will be apparent that the use of my invention results in great economy in the initial'cost of apparatus and in large savings in cost of operation, maintenance and repairs.

Having thus connection with described this invention inillustrative embodiments thereof, to the details of which do not desire to be limited, what is claimed as new and what is desired to secure by Letters Patent is set 'forth inthe appended claims.

' What I claim is 1. The method of treating sheet material consist-ing in feeding it into and out of a vac- 'uumchamber without breaking the vacuum,

then coating or impregnating the sheet material in the vacuum chamber, and then passing it through the vacuum chamber in a manner which will permit the fibers of the sheet material to dry under substantially little tension and not suiicient to cause the fibers to substantially rearrange themselves from their original position.

' 2. The method of treating a web of pa er consisting in feeding it into and out o a vacuum -chamber without breaking4 the vacuum, then coating or impregnating the web in the vacuum chamber, and then drying the coated or im regnated web in the vacuum chamber un er little or no tension, the tension being only suiicient to feed 'the web through the vacuum chamber and not sufficient to cause the fibers of the paper to substantially rearrange themselves from the interlaced position Iormed on thewire of the paper machine.

y3. The methdd of treating paper consisting in passin the paper into and out of a vacuum cham er continously Without breaking the vacuum, then sizing the paper in the vacuum chamber, and immediately drying the sized paper 1n the vacuum chamber under little or no tension, the tension being only sufficient to feed the paper through the vacuum chamber but not sufficient to cause the fibers of the paper to substantially rearrange themselves` from the position assumed 'by them on the` wire of the paper machine.

4. An apparatus 'for treating material inthe control h of the drying canI be closely standardized,

cluding a Vacuum chamber, means to permit the material to pass continously into and out of the Vacuum chamber Without breaking the vacuum, coating, coloring or impregnating means mounted in the vacuum chamber, and means to permit the material to dry in the vacuum chamber under little or n0 tension, the tension being sulicient to ,feed the material through the vacuum chamber but not sulicient to cause the constituent elements of the material to substantially rearrange themselvesl 5. An apparatus for treating a Web of paper including a vacuum chamber, means to permit the Web of paper to pass continuously into and out of the vacuum chamber Without breaking the vacuum, coating, coloring or impregnating means mounted in the Vacuum chamber, and means to permit the web of paper to dry in the vacuum chamber under little or no tension, the tension being sufli'cient to feed the Web ofI paper through the vacuum vchamber but notsuflicient to cause the fibers or" the Web to substantially rearand means to /inaaaaae Y range themselves-from the position that they assumed on the Wire 6. An apparatus for tre-ating material int cluding a vacuum chamber, means to permit the material to pass continuously into and outl of the vacuum chamber Without breaking the vacuum, coatin coloring, 0r impregnatmg means mounte in the vacuum chamber, permit the material to dry in folds or loops While it passes through the Vacuum chamber.

7. An apparatus for treating material including a vacuum chamber, means to permit the material to pass continuously into and out of the vacuum chamber Without breaking the Vacuum, coating, coloring or impnegnating means mounted in the vacuum chamber, and means to permit thematerial to dry in folds or loops and under little or no tension While it passes through the vacuum chamber and means to heat one or more of the folds OGDEN MINTON lor loops.

and under little or no tensionv 

